My 2014 981 Boxster S has issues with the PCM rebooting every 3 minutes or so, like in this thread, as of about 2 weeks ago. My PCM had already been updated for free 1-2 years ago during the recall, so I already have the latest firmware in my PCM. But since the didn't fix it for me, I suspected the HDD was bad. Found this thread and the other thread with the ISO for 4.76 PCM 3.1 update, so instead of the $3-5K to replace, I figured I try it.

Got me a 120G SSD from Amazon = $22, and started working on it early today (Sat). As several videos in youtube show, you only have to slide the radio out to expose the top of the PCM where the HDD lies ( ).

Once I got the HDD out, I downloaded and installed CloneZilla, to do a clone of the HDD into the new SSD. Note that your PC (I used Win10) needs two SATA USB adapters/docking stations so that you can plug each one (HDD and also the SSD) into available USB ports in your PC. Once you have your CloneZilla USB boot disk and boot into it, you can then follow instructions to clone the HDD into the SSD. I don't have to tell you, but I will: If you select the wrong target, you are dead in the water. Be extra careful!

Turns out my HDD was so bad, that the default CloneZilla settings failed in making a clone. I had to rerun it in the "dd" mode, or sector by sector, to even make it work.

Once I had the SSD ready, I tried it in my car, and it was "better" in that it now did a reset every 5min. I honestly was preparing for this, and it is why I had downloaded the ISO I mentioned above. Glad I did.

I first tried burning the DVD ISO image using DVD+R blank disks that I had laying around, but even after trying at various speeds, they never worked completely - the update would start, but error out.

I re-read the threads and caught that "everyone" that reported success used a Memorex DVD-R disk, so I made a trip to my local Walmart and bought a pack for $7. Sure enough this disk worked, although I had to run it 2-3 times until I got the "emergency repair" mode in which 100's of files were copied to the SSD.

Once I got the confirmation screen, I did the PCM reset (not that I had to), and waited. 5 min went by, then 10, then 15 - wow. No more resets!.

Just now came out from a wonderful drive with my wife (weather here in Texas was perfect blue sky, 65-67F!) and in the 1hour 45min drive, I NEVER got a single reset.

Once thing I noticed before I started the repairs: I had lost the navigation function - loading maps didn't work. This was my other indicator that something was seriously wrong with the HDD. Well, that is still the case after the SSD and system restore to 4.76 (same I started with), which as I expected from reading the other threads, does nothing for the nav/maps - that is yet another DVD to make that work - $200-300 from what I have found so far. Once I try this fix for a while longer, I will consider finding/buying the map DVD to see if that restores the navigation functionality.

At any rate, I am feeling pretty good. $30 out of pocket vs $3k+ for a replacement, for about 2-3 hours of trying the update 5-6 times - not bad in my book.

 

I did all of this and it was a pain. But definitely worth all of it. I ended up using a local computer repair because my hardrive was shot. It also didnt complete the update to 100% but its at version 4.76. Today i drove for a few hours and it was a great feeling to have the radio with out any issues!

 

Wish someone with Windows 11 could comment on this. I can only burn the original single ISO file to my DVD, but the update process doesn't actually upgrade me to 4.76. It stays stuck on my old azz 2.74 or whatever. When I unzip or extract the single large ISO file and get all the folders and files shown in these Mac screenshots, I can't select all of them at once and burn to the DVD the same way I can with ISOBURN (program)....

 

Yeah I got the ISO / file image, I'm gonna have to go post somewhere else maybe to get more attention to this maybe but no matter what I do, I can't get my PCM to update to v4.76. I've tried 3 different times and ways to burn the file(s) to the DVD on my Windows 11 desktop. The burning "works" in the sense that it's successful, and the car PCM recognizes the DVD and begins the update. Only problem is, after the update is successful, it says "you've successfully updated to v2.74!" sigh

I tried burning the single .ISO file, I tried unpacking/unzipping the .rar ISO file and then burning all the files/folders to the DVD etc. Each time resulted in the same scenario I described: successful file burn to DVD, vehicle PCM recognizes as update DVD and begins process, process finishes and I am right back where I started. No update actually applied.

 

It looks like you have an older version V2 of the PCM3.1 that can only be upgraded to V2.74. The latest version of the PCM3.1 (V4) is in later 2013 thru 2016 and it can be upgraded to V4.76. The V4 has the Jukebox and some other features that the earlier versions do not have. I have included some information on the different versions.
Jim

 

Wow thanks a ton for all of that info. That's amazing. That's incredibly detailed and explains everything! Makes sense and just confirms I'm kinda SOL. No way in hell I'm going to entertain paying any kind of insane price for a newer generation PCM from Porsche with my VIN and probably have to have it all reprogrammed to my VIN by the dealer themselves etc etc.

It's either the iSudar retrofit setup for me now after I return this retro**** GTA Car Kit. Or do the full aftermarket head unit route i.e. Pioneer 2660NEX unit and the adapter/harness kit required to hook it all up to the factory stuff for full functionality. That costs a lot too, but would be way less than anything from Porsche for sure.

 

If you decide to go with the iSudar or another retro I would make sure it will work with your older V2 PCM with V2.74.
Jim

 

Oh great, is that an issue to be concerned about now too? I mean, are there other documented cases of compatibility problems with my V2 PCM w/ v2.74?

FWIW, I had the GTA Car Kit retrofit setup installed and only got it to work once (reinstalled it 3x) for about 15 minutes before crashing/flickering & dead black screen again. So I think I should be OK with an iSudar kit no?.... lol I don't want to spend $1000 on the aftermarket head unit route through Car Toys if I don't have to...

 

I have 2015 991.1 Targa 4S with PCM3.1 - Version 4.52. Does anyone know what the differences are to 4.76? What would I gain with upgrade?

 

TBH I think most of these PCM updates are a wash unless you're having specific issues or problems. And for what Porsche officially charges, I'd throw that money at an aftermarket head unit instead.

 

AFAIK you get more reliable/stable bluetooth connectivity on music playback from you phone and cell connection.
The upgrade to 4.76 in you case is pretty straight forward with the iso image provided in this thread.

 

Just burned v4.76 and upgraded fine. I had to use a 4x DVD+RW Verbatim 4.7GB disc (part Verbatim#94520 1016-203) and burn at 4x rather than the other 16x newer ones that cause the security check errors as noted above.
Note after install I think it pays to do the 'Reset PCM Vehicle Handover' this also clears some other stuff and stops that "voltage warning shutdown" coming on if you turn ignition to on.
Thanks for supplying and maybe one day Porsche may enter the 21st century and allow update by USB

 

My 2011 Cayenne had a sony stereo which i changed out back to the original head unit. I checked the software version and it was 2.20. How do i upgrade this software to the latest 4.76 version?

 

Visit your dealer. However, That is probably not a PCM 3.0 or PCM 3.1 so you probably won't get to V4.xx. Check the Cayenne threads, but depending on whether you are PCM2 or PCM 3, there will be a different max version number.

 

I have the 3.1 pcm

I rang my local Porsche dealer and was no help at all. He said they had no update for mine anymore as it was an old model haha...